"I hate that argument too" is "I also hate that argument" which is the same thing as "I hate the same argument that you hate, the one you just said that I'm directly replying to" which is the same as "I agree."

Literacy crisis is real.

Edit: But thanks for explaining it, though I find it unconvincing. Do people really not know how to read "too" in this context? And with such confidence to downvote?